I am a new Assistant Professor in the Department of Pharmacology and Feist-Weiller Cancer Center at Louisiana State University (LSU). LSU has a strong focus on translational research, and has rich opportunities to teach medical and graduate students. My immediate career goals are to secure funding to further develop the project described below in order to compete for R01 funding within the next 2 years. Long-term goals include collaborating with other investigators at LSU on human chemoprevention clinical trials, in addition to conducting my own research project. I intend to stay in academia and mentor students. This K-22 Career Transition Award will enable me to study the extent and mechanisms of the inhibitory effects of naturally occurring coumarins (NOCs) and 1'-acetoxychavicol acetate (ACA) in human and rodent models of mammary carcinogenesis. We hypothesize that these compounds will be effective at blocking a broad range of activities in the carcinogenic process, from the early stages (initiation) to the later stages (promotion/ progression). The specific aims are: 1) To determine the role(s) of GST induction and/or P450 inhibition on NOCs' inhibitory effects on mammary tumor initiation; 2) Determine the roles of ornithine decarboxylase inhibition (ODC, a putative oncogene involved in transformation), cell proliferation, and induction of apoptosis in the effects of auraptene and ACA on mammary carcinogenesis in female rats treated with the direct-acting carcinogen N-methylnitrosourea; and 3) To further examine the mechanisms of ODC inhibition and induction of apoptosis induced by auraptene and ACA. Several approaches will be used to determine whether these compounds affect the transcriptional regulation of ODC, and whether the inhibition of ODC leads to the induction of apoptosis. Since NOCs and ACA are abundant in the human diet (citrus fruits, celery, ginger) they have the potential to impact human cancer risk. Notably, these natural products possess a range of beneficial anticarcinogenic activities worthy of further study.